LM2676SX-3.3/NOPB National Semiconductor, LM2676SX-3.3/NOPB Datasheet

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... The output voltage is guaranteed to a ±2% toler- ance. The clock frequency is controlled to within a ±11% tolerance. Typical Application SIMPLE SWITCHER ® registered trademark of National Semiconductor Corporation © 2008 National Semiconductor Corporation ® High Efficiency 3A Step-Down Features ■ Efficiency up to 94% ■ ...

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Connection Diagrams and Ordering Information TO-263 Package Top View Order Number LM2676S-3.3, LM2676S-5.0, LM2676S-12 or LM2676S-ADJ See NSC Package Number TS7B Ordering Information for LLP Package Output Voltage Order Information 12 LM2676SD-12 12 LM2676SDX-12 3.3 LM2676SD-3.3 3.3 LM2676SDX-3.3 5.0 LM2676SD-5.0 ...

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... Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Input Supply Voltage ON/OFF Pin Voltage Switch Voltage to Ground (Note 12) Boost Pin Voltage Feedback Pin Voltage Power Dissipation Electrical Characteristics of operation, −40°C to 125°C. Specifications appearing in normal type apply for T LM2676-3 ...

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All Output Voltage Versions Electrical Characteristics Limits appearing in bold type face apply over the entire junction temperature range of operation, −40°C to 125°C. Specifications appearing in normal type apply for T justable versions and V =24V for the 12V ...

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Note 1: Absolute Maximum Ratings are limits beyond which damage to the device may occur. Operating Ratings indicate conditions under which of the device is guaranteed. Operating Ratings do not imply guaranteed performance limits. For guaranteed performance limits and associated ...

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Typical Performance Characteristics Normalized Output Voltage Efficiency vs Input Voltage Switch Current Limit www.national.com 10091409 10091411 Operating Quiescent Current 10091404 6 Line Regulation 10091410 Efficiency vs I LOAD 10091412 10091405 ...

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Standby Quiescent Current 10091440 ON/OFF Pin Current (Sourcing) 10091414 Feedback Pin Bias Current 10091416 ON/OFF Threshold Voltage Switching Frequency 7 10091413 10091415 www.national.com ...

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Typical Performance Characteristics Continuous Mode Switching Waveforms V = 20V 5V OUT μ 200 μF, C OUT A: V Pin Voltage, 10 V/div Inductor Current, 1 A/div C: Output ...

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Block Diagram * Active Inductor Patent Number 5,514,947 † Active Capacitor Patent Number 5,382,918 9 10091406 www.national.com ...

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... LM267X Made Simple (version 2.0) a complete switching power supply can be de- signed quickly. The software is provided free of charge and can be downloaded from National Semiconductor's Internet site located at http://www.national.com. SWITCH OUTPUT This is the output of a power MOSFET switch connected di- rectly to the input voltage ...

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FIGURE 2. Basic circuit for adjustable output voltage applications Power supply design using the LM2676 is greatly simplified by using recommended external components. A wide range of inductors, capacitors and Schottky diodes from several manufacturers have been evaluated for use ...

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When parallel combinations of capacitors are re- quired it has been assumed that each capacitor is the exact same part type. The RMS current and working voltage (WV) ...

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Step 2: Set the output voltage by selecting a fixed output LM2676 (3.3V 12V applications) or determine the re- quired feedback resistors for use with the adjustable LM2676 −ADJ Step 3: Determine the inductor required by using one ...

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From Table 1, L38 in a surface mount component is available from Pulse Engineering with part number PE-54038S. Step 4: Use Table 6 to determine an output capacitor. With a 14.8V output the 12.5 to 15V row is used and ...

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Inductor Selection Guides For Continuous Mode Operation FIGURE 3. LM2676-3.3 FIGURE 4. LM2676-5.0 10091421 10091422 15 10091423 FIGURE 5. LM2676-12 10091424 FIGURE 6. LM2676-ADJ www.national.com ...

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Inductor Inductance Current Reference (µH) Number L23 33 1.35 L24 22 1.65 L25 15 2.00 L29 100 1.41 L30 68 1.71 L31 47 2.06 L32 33 2.46 L33 22 3.02 L34 3.65 15 L38 68 2.97 L39 47 3.57 L40 ...

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Capacitor Selection Guides Capacitor AVX TPS Series Reference C (µF) WV (V) Code C1 330 C2 100 C3 220 100 C10 22 C11 C12 C13 Capacitor Sanyo OS-CON SA ...

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Nichicon Panasonic AVX Sprague/Vishay Sanyo Kemet Table 3. Output Capacitors for Fixed Output Voltage Application Output Inductance Voltage (V) (µ 3 100 Output ...

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Output Inductance Sanyo OS-CON SA Voltage (V) (µH) Series No 100 1 No. represents the number of identical capacitor types to be connected in parallel C Code ...

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Output Inductance Sanyo OS-CON SA Voltage (V) (µH) No 100 * Check voltage rating of capacitors to be greater than application input voltage. No. represents the number of identical capacitor types to be ...

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Output Voltage Inductance (V) (µ 6. 100 12.5 68 100 33 ...

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Output Voltage Inductance (V) (µ 6. 100 12.5 68 100 33 ...

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Physical Dimensions inches (millimeters) unless otherwise noted TO-263 Surface Mount Power Package Order Number LM2676S-3.3, LM2676S-5.0, LM2676S-12 or LM2676S-ADJ NS Package Number TS7B 23 www.national.com ...

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TO-220 Power Package Order Number LM2676T-3.3, LM2676T-5.0, LM2676T-12 or LM2676T-ADJ NS Package Number TA07B 14-Lead LLP Package NS Package Number SRC14A 24 ...

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Notes 25 www.national.com ...

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